Method of heating and handling liquids



3 F. w. MILLER Q 2,309,523

METHOD OF HEATING AND HANDLING LIQUIDS Driginal Filed 001:. 20, 1938 REF/LL WHSHOUT THNK Patented Jan. 26, 1943 UNITED STATES METHOD OF HEATING AND HANDLING LIQUIDS Frank W. Miller, Chicago,

111., assignor to Franclare Company, Chicago, Ill., a corporation of Illinois Continuation of application Serial No. 236,009, October 20, 1938. This application November 5, 1941, Serial No. 417,929

1 Claim.

This application is a continuation of pending application Serial No. 236,009, filed October 20, 1938, as a division of my then pending application, Serial No. 195,861, filed March 14, 1938, which eventuated in Patent No. 2,135,407, issued November 1, 1938, in which is disclosed an apparatus for washing and refilling boilers by which the present method may be practiced for that purpose.

While the apparatus of said patent is here also shown as exemplifying a means by which my method may be practiced, it should be understood that my method is capable of heating and handling liquids for use for various purposes other than the refilling of boilers and that apparatus, differing widely in structure from that disclosed, may be utilized in the practice of this method,

The primary purpose of my present invention is to provide a method by which a quantity of liquid, dependent in volume upon the quantity of heat available, may be heated, stored and made available for use at a predetermined temperature.

Since a boiler washing and filling system is here disclosed merely to illustrate the princi: ples of my invention, the water employed in such a system and mentioned throughout the specification should be understood to be symbolical merely of any liquid which it may be desired to heat and handle in accordance with my method.

Referring to the drawing,

The single figure is a schematic illustration of an apparatus by which the principles of my invention may be made effective.

Referring to the drawing more in detail, reference character I indicates a washout tank and 2 arefill tank, both of suitable size and construction for the purposes required. The blown off steam and water from a locomotive being blown down are delivered from the boiler through a blow-oif line 3 into a separator 4 by which the steam and water are separated, the blow-off water being delivered from the separator through a pipe 5 into the washout tank I where it is stored for future washout purposes, and the blown off steam being delivered from the top of the separator through a pipe 6 into one or more heat exchangers I and 8 which may be either of the closed or open type but are here illustrated as open type condensers. In apparatus designed for heating and storing liquid for other purposes, the steam supplied through pipe 6 may be either exhaust or live steam derived from any suitable source. Other heating Cit media thansteam and liquid heaters of various types other than steam heat exchangers are also within the'purview of my invention;

The sludge may be delivered-from the separator 4 through a pipe 9 and drain H to the sewer or other disposal means, a hand valve 12 being provided as a normal shut-off adapted to be opened when cleaning of the separator becomes necessary.

The water stored in washout tank l is withdrawn therefrom when required by a washout pump I3, the suction side of which is connected to the tank through suitable piping I l, the discharge from the pump being delivered through a pipe line 15 to the washout line it extending to the roundhousev stalls and connected at its extreme end-with a return circulating line I! discharging back into the tank i. Pipe M is equipped with the usual check valve is and hand valve I 9. Pipe I5 is provided with a hand valve 2|, and a cross, connecting pipe 22 between pipe l5 and pipe 9 affords provision for delivering wa ter to the separator 4 for flushing purposes when valve 23 is opened.

The speed of washout pump I3 is controlled by a pressure governor 24 connected by pipe 25 with the delivery line I5. Steam to operate pump I3 is supplied through a branch 20 from a main steam line 21 extending from the power boilers of the installation.

Tempering of the washout water so that it will not be delivered to the washout nozzle at a temperature higher than can be comfortably handled by the operator is accomplished by admitting cold water to the intake of the washout pump through a branch line 28 emanating from a cold fresh water supply line 20.- A thermostatic valve 3! in the branch 23 is tl1ermostaticaly controlled through a suitable connection 39 by the. temperature of the washout water delivered through the line [5. Surplus water above apredetermined level in the washout tank is delivered to a sump or drain trench 32 by a siphon-shaped overflow 33, the intake end of. which is disposed near the bottomof the tank so that the overflow will be withdrawn from the coldest portion of the tank and the pitting of the lower portion of the tank walls occasioned by stagnant water will be reduced. To prevent emptying of the washout tank by siphonic action, the crown of the overflow is equipped with a vent pipe 34. water level is maintained in the washout tank by admitting fresh water from the supply line 29 under the control of a balanced valve 35 A predetermined minimum arranged to be opened and closed by a float 36 connected with the tank at substantially the height at which it is desired to maintain a minimum water level.

The blown off steam delivered to the heat exchangers 1 and 8 through the pipe 6 from the separator 4 is condensed therein, and its heat units are transferred to the refill water by circulating the refill water through the exchangers during the blowing off operation. For this purpose a circulating pump 31 has its suction side connected by a pipe 38 with the refill tank 2 below the minimum water level maintained therein and its delivery side connected through a pipe 39 with the heat exchangers l and B, the ends of the branch pipes 4| entering these condenser heaters being equipped with spray nozzles which disperse the water throughout the steam filled chambers, thereby enhancing the condensation of the blown off steam and the heating of the circulated water. From the heat exchangers the water and condensed steam are returned to the refill tank through a pipe line 42. Thus, it will be seen that the heat units of the steam supplied to the heaters are transferred to the refill water stored in the tank 2.

A predetermined minimum water level is maintained in the refill tank by a balanced valve 43 interposed in a branch 44 from the cold water line 29, but the maintained level instead of being near the top of the tank, as has heretofore been customary, is near the bottom of the tank under the control of a float 45 by which the valve 43 is actuated. Normally, therefore, after a refill operation and before a subsequent blowofi operation, the refill tank will contain only a relatively small quantity of water, the minimum amount of which is determined by the float 45. When a blow-01f operation now takes place, the refill water circulated from the tank through the heat exchangers will be heated therein by the blown off steam, thus raising the temperature of the small amount of refill water stored in the tank so that this water will soon be raised to a temperature approaching the boiling point.

When, however, the temperature of the refill water of the tank has reached approximately 200 F., fresh water is admitted to the tank through a branch 46 connected with the cold water line 29. The supply of water through branch 46 is regulated by a thermostatic valve 4! under the control of the thermostat 48 which is subjected to the temperature of .the water in the tank. Th admission of cold water to the tank counteracts or precludes any further rise in temperature of the refill water above that for which the thermostatic valve is set, with the result that as the blow-ofi operation proceeds, the temperature of the refill water in the tank will remain substantially constant while the volume thereof will increase in accordance with the heat units transferred to the refill water by the blown off steam. Similarly, when heating liquid for other purposes, the stored liquid will be circulated through the heater or otherwise heated until the temperature of the stored liquid reaches the predetermined maximum, whereupon fresh unheated liquid is admitted under thermostatic control to the storage tank to increase the quantity of stored liquid without reducing the temperature thereof below the predetermined maximum.

It will be manifest, therefore, that, instead of wasting water and heat units, as has heretofore been the case when the refill tank was substantially full at the beginning of a blowingoff operation, or instead of wasting the heat units of the blown 01f steam, as has heretofore occurred when the reaching of the overflow level in the refill tank occasioned the shutting off of the supply of condensing water, my novel method which contemplates a low water level in the refill tank at the start of a blow-off operation insures the utilization of all the heat units of the blown off steam for heating refill water and without any wasting of water during any normal blow-off. Furthermore, it insures that the refill water in the tank will be at approximately 200 which is a desirable temperature for refilling purposes or, in other words, the stored refill water is as hot as can be handled by the refill pump.

Should an unusual number of boilers be blown off simultaneously or in succession or should an excess of heating steam from other sources be delivered to the condenser before a refill operation takes place, the capacity of the refill tank will, of course, eventually be reached, and in such event, loss or waste of heated water through the tank overflow is prevented by shutting off the further delivery of water to the tank through branch 46 through the instrumentality of a shutoff valve 49 interposed in pipe 46 and controlled by a float 5| located at the maximum water level height of the tank overflow. This overflow is indicated on the drawing by reference character 52 and is adapted to discharge into a sump or trench 53 in the usual manner.

Under such circumstances, the refill tank will be substantially full of refill water at a temperature approximating 200 F., and if blowing off should continue beyond this point, no further water will be added to the tank, but the temperature of the large volume of stored water will be gradually increased by the continued transfer thereto of blown ofi steam heat units until the tank contents are at boiling temperature. Beyond this point, the surplus steam is permitted to escape to atmosphere through the vent pipe 50. This condition in which loss of heat units of blown oif steam would occur could only arise under most unusual and infrequent circumstances where it became necessary to blow off an unusually large number of boilers before proceeding with any refilling.

The stored hot water in the refill tank is withdrawn therefrom for refilling purposes through a suction pipe 54 by a refill pump 55 which discharges through a pipe 56 into the refill line 51 extending through the roundhouse. In the unusual event that the refill water in the tank should be in such close proximity to the boiling point that it could not be efficiently handled by the refill pump, the temperature thereof is reduced by admitting cold water to the suction side of the pump through a branch 58 from the cold water line 29, this admission being controlled by a valve 59 thermostatically influenced by a thermostat GI located in the discharge pipe 56.

To maintain at all times a supply of hot water at the drops, the end of the refill line is connected with a return circulating line 62 which discharges through a spray nozzle into one of the heat exchangers, as 8 for instance. The exhaust steam from the washout and refill pumps is delivered through branches 63 and 64, respectively, to an exhaust pipe 65 which is connected by a branch 68 with the heat exchanger 8 so that when no blow oiT is taking place the exhaust steam from the pumps will be condensed by the refill circulating water delivered from circulating line 62, which water and the steam condensed thereby will be returned through pipe 42 to the refill tank. As a precaution against the production of excessive pressure in the exhaust pipe 65 or in the heat exchangers, the exhaust pipe is preferably equipped with a pressure relief valve 61. Steam for operating the refill pump is supplied from the main steam line 21 through a branch pipe 68, and the speed of the pump is controlled by a pressure governor 69.

It should be apparent from the foregoing that I have provided a system in the operation of which neither water nor steam will be wasted, but which will utilize all the heat units of the blown off steam for heating refill water and which will insure after each blow-01f operation a supply of hot refill water approximately 200 in temperature. The waste and inefficiencies of prior practices are eliminated, with the result that my novel system is highly efiicient and satisfactory in operation.

The structural details illustrated and described are manifestly illustrative only and are capable of wide modification and variation without exceeding the scope of my invention as defined in the following claim. For instance, while the washout and refill piunps are shown as being steam operated, they may if preferred be electri cally driven in accordance with the tendency of modern practice.

I claim:

The method of blowing down and refilling boilers with fresh water at a predetermined temperature heated by steam from said boilers so as to maintain a supply of fresh water at a suinciently high temperature and containing approximately the amount of heat to provide for refilling the boilers being worked upon with water at said predetermined temperature, which method comprises, storing a predetermined minimum amount of fresh water in a storage chamber when no boilers are being worked upon, blowing down one or more boilers and separating steam from the water removed from said boilers, withdrawing Water from said storage chamber, pass.- ing said withdrawn water through a steam con denser and returning said withdrawn water to said chamber, supplying said separated steam to said condenser to heat the water being returned to said chamber, adding fresh relatively cold water to said chamber when the temperature of the water in said chamber exceeds said predetermined temperature, said fresh cold water being added in an amount suflicient to approximately maintain said predetermined temperature to thereby increase the volume of water in said chamber at said predetermined temperature, discontinuing the addition of said fresh cold Water to said chamber when the number of boilers being worked upon causes the volume of water in said chamber toapproach the capacity of said chamber thereby causing the temperature of the water in said chamber to increase without substantial increase in volume, refilling said boilers directly from said chamber when the water therein is at said predetermined temperature, and adding suflicient fresh relatively cold Water to the refill Water during its passage to said boilers from said chamber when the temperature of the water in said chamber exceeds said predetermined temperature to bring the refill water to approximately said predetermined temperature before delivery into said boilers. FRANK W. MILLER. 

